# tricky electric potential [closed]

I have this question: $q_1$ is a Uniformly Charged long Wire(inf in z axis) with $\lambda$ (charge per unit length).
In (0,0,0) I have A very long conducting cylinder of radius a (also inf in z axis). NOT GROUNDED!!!
I want to find the electric potential everywhere. Where do i start? thanks!

PICTURE:

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## closed as too localized by David Z♦May 8 '13 at 17:22

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Is there a pre-existing charge on the cylinder? –  Jim May 8 '13 at 14:55
no, the cylinder is neutral. –  Eli May 8 '13 at 14:58
I would recommend image charges, that should work rather well in this case. See here en.wikipedia.org/wiki/Method_of_image_charges. –  Noldig May 8 '13 at 15:04
hi Noldig! your suggestion is very helpfull when the cylinder is GROUNDED, but in this case the cylinder is NOT GROUNDED. –  Eli May 8 '13 at 15:07
@Eli: Plz see question again have they anywhere defined zero potential? NO. So, just define zero potential on the cylinder and calculate potentials of other space using Method of Images. –  ABC May 8 '13 at 15:55